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Modeling blood flow in Veins of Uniform Properties (Giraffe Jugular Vein)

Open Journal of Biophysics 2024年第2期14卷 132-153页

作者： Rogers Omboga Amenya Johanna Kibet Sigey Geoffrey Moriaso Ole Maloiy David Mwangi Theuri Department of Mathematics and Physical Sciences Dedan Kimathi University of Technology Nyeri Kenya Department of Pure and Applied Mathematics School of Mathematical Sciences Jomo Kenyatta Unversity of Agriculture and Technology Kisii Kenya Institute of Animal Physiology and Biotechnology Research University of Nairobi Nairobi Kenya

This paper models the giraffe’s jugular veins as a uniform collapsible tube from a rigid skull. The equations governing one-dimensional steady flow through such a tube for various conditions have been developed. The effects of inertial and inclination angles that have not been discussed previously have been included. It has been shown that different flows for a uniform tube (vein) are possible. However, this flow matches that of a jugular vein which is supercritical, and the steady solution has been given by the balance between the driving forces of gravity and the viscous resistance to the flow at the right atrium of the heart must be sub-critical for a fixed right-atrium pressure which means that an elastic jump is required to return the flow to sub-critical from the supercritical flow upstream this type of relationship gives rise to flow limitation at the same time given any right atrium fixed pressure there exists a maximum flow rate which when exceeded the boundary conditions of the flow do not hold boundary conditions at the right atrium are not satisfied hence making the steady flow impossible this mechanism of flow limitation is slightly different from the other one in that causes airways through forced expiration from the observation made it is clearly shown that there is an intravascular pressure difference with a change in height.

关键词： blood flow Jugular Vein Cross-Sectional Area Supercritical Subcritical Jump

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Dynamic Non-Invasive Detection of NADH Based on blood flow-Mediated Skin Fluorescence (FMSF) Method

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Open Journal of Applied Sciences 2024年第6期14卷 1437-1453页

作者： Peng Liu Tengfei Bi Gongzhi Du Long Yan Huayi Hou Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of Technology Wuhan China

Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as a function of time in response to blocking and releasing of blood flow in a forearm are used as a measure of oxygen transport with blood to the tissue, which directly correlates with the skin microcirculation status. In this paper, a non-invasive dynamic monitoring system based on blood flow-mediated skin fluorescence (FMSF) technology is developed to monitor the NADH fluorescence intensity of skin tissue during the process of blocking reactive hyperemia. Simultaneously, laser speckle contrast imaging (LSCI) and laser Doppler flowmetry (LDF) were used to observe blood flow, blood oxygen saturation (SOt2) and relative amount of hemoglobin (rHb) during the measurement process, which helped to explore NADH dynamics relevant physiological changes. A variety of parameters have been derived to describe NADH fluorescence curve based on the FMSF device. The experimental results are conducive to understanding the NADH measurement and the physiological processes related to it, which help FMSF to be a great avenue for in vivo physiological, clinical and pharmacological research on mitochondrial metabolism.

关键词： Reduced Nicotinamide Adenine Dinucleotide (NADH) flow-Mediated Skin Fluorescence (FMSF) Laser Doppler flowmetry (LDF) blood flow

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Thermogram-based estimation of foot arterial blood flow using neural networks

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 325-344页

作者： Yueping WANG Lizhong MU Ying HE School of Energy and Power Engineering Dalian University of TechnologyDalian 116023Liaoning ProvinceChina State Power Investment Corporation Northeast Electric Power Co. Ltd.Shenyang 110181China

The altered blood flow in the foot is an important indicator of early diabetic foot ***,it is challenging to measure the blood flow at the whole foot *** study presents an approach for estimating the foot arterial blood flow using the temperature distribution and an artificial neural *** quantify the relationship between the blood flow and the temperature distribution,a bioheat transfer model of a voxel-meshed foot tissue with discrete blood vessels is established based on the computed tomography(CT)sequential images and the anatomical information of the vascular *** our model,the heat transfer from blood vessels and tissue and the inter-domain heat exchange between them are considered thoroughly,and the computed temperatures are consistent with the experimental *** data are then used to train a neural network to determine the foot arterial blood *** trained network is able to estimate the objective blood flow for various degrees of stenosis in multiple blood vessels with an accuracy rate of more than 90%.Compared with the Pennes bioheat transfer equation,this model fully describes intra-and inter-domain heat transfer in blood vessels and tissue,closely approximating physiological *** introducing a vascular component to an inverse model,the blood flow itself,rather than blood perfusion,can be estimated,directly informing vascular health.

关键词： diabetic foot thermal analysis blood flow inverse method neural network

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A Discontinuous Galerkin Method for blood flow and Solute Transport in One-Dimensional Vessel Networks

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Communications on Applied Mathematics and Computation 2022年第2期4卷 500-529页

作者： Rami Masri Charles Puelz Beatrice Riviere Department of Computational and Applied Mathematics Rice UniversityHoustonTX 77005USA Department of Pediatrics-Cardiology Baylor College of MedicineHoustonTX 77030USA

This paper formulates an efficient numerical method for solving the convection diffusion solute transport equations coupled to blood flow equations in vessel *** reduced coupled model describes the variations of vessel cross-sectional area,radially averaged blood momentum and solute concentration in large vessel *** the discretization of the reduced transport equation,we combine an interior penalty discontinuous Galerkin method in space with a novel locally implicit time stepping *** stability and the convergence are *** results show the impact of the choice for the steady-state axial velocity profile on the numerical solutions in a fifty-five vessel network with physiological boundary data.

关键词： Reduced models blood flow Solute transport Coriolis coefficient Vessel networks Junction conditions Locally implicit

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Oxytocin improves testicular blood flow without enhancing the steroidogenic activity in Baladi goats

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Asian pacific Journal of Reproduction 2022年第5期11卷 223-230页

作者： Mohamed G.Hedia Amr S.El-Shalofy Department of Theriogenology Faculty of Veterinary MedicineCairo UniversityGiza 12211Egypt

Objective:To investigate the effects of a single oxytocin injection on plasma steroid concentrations,testicular blood flow measures(resistive and pulsatility indexes),and testicular echogenicity in Baladi ***:Twelve Baladi goat bucks were randomly allocated into 2 groups and received an intravenous injection of either 0.7 IU/kg oxytocin or normal saline 0.9%.Venous blood samples were collected,and testicular blood flow Doppler parameters(i.e.,peak systolic velocity,end-diastolic velocity,time average maximum velocity,resistive index,and pulsatility index)were assessed for supratesticular arteries in the left and right testes immediately before(0),and at 5,30,60,and 120 min after ***:Plasma concentrations of testosterone significantly decreased in the oxytocin group at 60 min post-treatment compared to the control group,whereas plasma concentrations of estradiol-17βwere not affected(P>0.05).Both resistive index and pulsatility index declined in the oxytocin group at 60 min post-treatment compared to the control group(Pblood flow and decreases plasma testosterone concentrations in male Baladi goats.

关键词： Bucks blood flow Doppler Estradiol-17β Goat Oxytocin Testicular artery Testosterone

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AKG/OXGR1 promotes skeletal muscle blood flow and metabolism by relaxing vascular smooth muscle

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Life Metabolism 2022年第3期1卷 285-297页

作者： Jinping Yang Guli Xu Yiming Xu Pei Luo Yexian Yuan Lin Yao Jingjing Zhou Yunlong Zhu Ishwari Gyawali Chang Xu Jinlong Feng Zewei Ma Yuxian Zeng Songbo Wang Ping Gao Canjun Zhu Qingyan Jiang Gang Shu Guangdong Laboratory for Lingnan Modern Agriculture and Guangdong Province Key Laboratory of Animal Nutritional Regulation South China Animal Nutrition and Feed Science Observation and Experimental StationCollege of Animal ScienceSouth China Agricultural University483 Wushan RoadTianhe DistrictGuangzhouGuangdong 510642China School of Basic Medical Sciences The Sixth Affiliated Hospital of Guangzhou Medical UniversityQingyuan People’s HospitalGuangzhou Medical UniversityGuangzhouGuangdong 511518China South China Research Center for Acupuncture and Moxibustion Medical College of Acu-Moxi and RehabilitationGuangzhou University of Chinese MedicineGuangzhouGuangdong 510006China School of Pharmaceutical Sciences Guangzhou University of Chinese MedicineGuangzhouGuangdong 510006China

In response to contraction during exercise,skeletal muscle growth and metabolism are dynamically regulated by nerve action,blood flow,and metabolic feedback.α-Ketoglutarate(AKG),a bioactive intermediate in the tricarboxylic acid cycle released during exercise,has been shown to promote skeletal muscle ***,the underlying mechanism of AKG in regulating skeletal muscle development and metabolism is still less known.2-Oxoglutarate receptor 1(OXGR1),the endogenous AKG receptor,is found to be distributed in the vascular smooth muscle(VSM)of skeletal ***1 knockout results in skeletal muscle atrophy,accompanied by decreased expression of myosin heavy chain I(MyHC I),capillary density,and endurance exercise ***,the study found that dietary AKG supplementation increased mice endurance exercise distance,MyHC I/MyHC IIb ratio,arteriole,and capillary densities in skeletal ***,acute AKG administration gradually increased the blood flow in the lower ***,by using OXGR1 global knockout and OXGR1 VSM-specific(MYH11-Cre×OXGR1-FloxP)knockdown models,we found that OXGR1 in VSM is essential for AKG-induced improvement of skeletal muscle *** to the in vitro study,AKG expanded the cell area in VSM with a decreased intracellular pH by *** results demonstrated a novel role of AKG/OXGR1 in VSM of skeletal muscle to regulate blood flow and then enhance slow muscle fiber conversion and *** findings provide a theoretical basis for the AKG/OXGR1 signaling pathway to maintain human muscle function and improve meat production and livestock and poultry meat quality.

关键词： OXGR1 AKG smooth muscle cell skeletal muscle blood flow metabolism

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blood flow Through a Catheterized Artery Having a Mild Stenosis at the Wall with a blood Clot at the Centre

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Computer Modeling in Engineering & Sciences 2020年第11期125卷 565-577页

作者： Anber Saleem Salman Akhtar Sohail Nadeem Alibek Issakhov Mehdi Ghalambaz Mathematics and Its Applications in Life Sciences Research Group Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics Quaid-i-Azam UniversityIslamabad45320Pakistan Al-Farabi Kazakh National University Faculty of Mechanics and Mathematicsav.al-Farabi71AlmatyKazakhstan Institute of Research and Development Duy Tan UniversityDa Nang City550000Vietnam Faculty of Electrical-Electronic Engineering Duy Tan UniversityDa Nang City550000Vietnam

The blood flow through a catheterized artery having a mild stenosis at the wall together with a blood clot at the centre is studied in the current *** can occur in vessels carrying blood to brain(i.e.,Carotid arteries),Renal arteries that supply blood to kidneys *** flow is refined in such vessels by application of *** have used a Newtonian viscous fluid model and also distinct shapes of stenosis,(i.e.,symmetric and non-symmetric shapes)are considered for this *** entropy generation togetherwith viscous dissipation is also taken into account for a complete description of heat transfer *** solutions are calculated for the problem subject to given“no slip conditions”.The results are discussed *** velocity quickly increases for a non-symmetric stenosis as compared to a symmetric *** the height of mild stenosis increases and the channel becomes narrow then the velocity increases in the centre but it decreases with the stenosed ***,as the height of blood clotσincreases then the velocity of blood flow reduces with the wall having clot but it remains almost same with the stenosed *** are plotted to visualize the flow *** trapping is symmetric for a symmetric stenosis shape but it changes to non-symmetric trapping when we have a non-symmetric shape of stenosis.

关键词： blood flow catheter stenosed artery blood clot entropy

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blood flow AND MACROMOLECULAR TRANSPORT IN CURVED blood VESSELS

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Applied Mathematics and Mechanics(English Edition) 2006年第9期27卷 1223-1231页

作者：魏兰温功碧谭文长 Department of Mechanics and Engineering Science State Key Laboratory for Turbulence and Complex System Peking University Beijing 100871 P. R. China Institute of Applied Physics and Computational Mathematics Beijing 100088 P. R. China Department of Mechanics and Engineering Science State Key Laboratory for Turbulence and Complex System Peking University Beijing 100871 P. R. China

A numerical analysis of the steady/pulsatile flow and macromolecular （such as LDL and Albumin） transport in curved blood vessels was carried out. The computational results predict that the vortex of the secondary flow is time-dependent in the aortic arch. The concentration of macromolecule concentrates at the region of sharp curve, and the wall concentration at the outer part is higher than that at the inner part. Atherosclerosis and thrombosis are prone to develop in such regions with sharp flow.

关键词： curved blood vessels blood flow macromolecular transport atherosclerosis

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blood flow Simulation in the Femoral Artery

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Journal of Electronic Science and Technology 2018年第3期16卷 269-279页

作者： Camilo A.Naranjo Andrés F.Villa Juan C.Vélez Ricardo A.Prato Alberto J.Cadena Juan P.Tello IPATEC Institute CONICETBariloche R8400 Integra IT Bogotá 602 the Electronic and Electric Engineering Department Universidad del NorteBarranquilla 1569 the Institute of Mathematics Universidad de AntioquiaMedellin 050010 the Cardiology Department Clínica de la CostaBarranquilla 080020

This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood pressure and flow velocity in multiple instants of time and different places of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow approaches artery walls. In spite of all artery and blood flow properties not being considered, the values of pressure and velocity obtained are within the normal ranges. Finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick patients.

关键词： blood flow femoral artery finite elements Navier-Stokes pressure velocity

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Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 749-766页

作者： J.C.MISRA S.CHANDRA G.C.SHIT P.K.KUNDU Department of Mathematics Institute of Technical Education and ResearchSiksha O Anusandhan University Department of Mathematics Jadavpur University

The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.

关键词： blood flow electrohydrodynamic effect microfluidics channel flow

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